WASHINGTON — Rick Perry’s campaign was doomed by a number of major strategic miscalculations. Here are eight of the most important:

1) Underestimating the importance of debates.

Presidential primary debates hadn’t been important for the past 32 years (since Ronald Reagan destroyed George H.W. Bush with a single quip in Nashua, N.H.). They were in 2012. Perry hadn’t had a serious debate in a dozen years and he wasn’t ready for the debates to become Republican voters’ favorite reality TV show of 2011.

2) Preparation for a presidential campaign is really, really important

God may have called Rick Perry to run for president. But, as Perry joked this week, He didn’t tell the Texas governor he was going to win. You need to prepare the groundwork for a national campaign, from a grassroots organization to a media strategy. Perry jumped into the deep end of the pool. And he hadn’t yet learned to swim in the murky waters of presidential politics.

3) Running for president is not like running in Texas

The Texas electorate is not a cross-section of anything except the Lone Star State. Issues that resonate in Texas — and particularly the rhetoric and boastful nationalism — do not translate in other regions. (We mean Iowa and New Hampshire in particular.) The Texans who have transcended ”Texas-ism” have gotten elected: the Bushes. (They were born in New England, of course.) The Texified Texans — John Connally, Phil Gramm and Lloyd Bentsen — never got their campaigns off the ground.

4) Money does not buy happiness

Perry entered the race with a bang and raised more money than any other presidential candidate in the last three months of last year. But having more money in the bank on Jan. 1 — and spending more than anyone else in Iowa — didn’t ensure success. Message trumps money every time. (That is, if you have ENOUGH money to get your message out.)

5) Message discipline is vital

What was the theme of Rick Perry’s presidential campaign? There were dozens of them, it seemed. We had the jobs candidate, the electable candidate, the tough Texan, the family-values candidate, the gay-bashing candidate, the pro-immigration candidate, the Joe-Arpaio-immigrant-bashing candidate, the true conservative, the truest conservative, the authentic conservative and many, many more. When George W. Bush ran for president in 2000, he had one disciplined message: The compassionate conservative who would restore integrity to the White House, ”so help me, God.” Never wavered.

6) Underestimating the strength of other conservative candidates

On paper, Perry was the strongest conservative. Successful, job-creating governor of a big state. Proven money-raiser. Undefeated in nine elections. His strategists thought they could come in and steamroll the large group of conservative White House wannabes. They discovered that Herman Cain was more glib and more polished as a debater. Newt Gingrich rose from the political dead like a rotund Phoenix. Rick Santorum made a stronger connection with fundamentalist Protestants. Michele Bachmann, even as she was self-destructing on the campaign trail, delivered devastating attacks on Perry as a ”crony capitalist” who violated the rights of families by ”forcing” young girls to be immunized for a sexually transmitted disease.

7) Old stories can become new problems years after they first surface

Team Perry did not realize how much trouble a few old Texas news stories could become in a national campaign. Perry’s support for in-state tuition for children brought illegally into the U.S. by their parents became a hot-button issue — and Perry was pounded by Mitt Romney for being ”liberal” on immigration. The Texas governor compounded his problem by suggesting that critics of the in-state tuition were heartless. He also learned that the 2007 immunization story, long buried in Texas, would become a bigger story in Des Moines than it was in Dallas. Opposition research on yourself is vital. Perry didn’t respond quickly or effectively to controversies that were easily predictable (and should have been easy to deal with).

8) Organization is much more important than they thought

Mitt Romney’s been running for president for six years. Newt Gingrich has had a national political network for 30 years. They entered the race with political supporters in every state, which translated into political surrogates and fund-raising reach. Perry created the best Iowa organization money can buy (and he put together a pretty good one in South Carolina), but he couldn’t build one in the other 47. (We give him a pass in Texas.) Evidence of his weak national organization: He couldn’t muster the necessary signatures to qualify for the March 6 primary ballot in Virginia.